Concentration of nonsulfide, nonsilicate ores with nitric acid treated fatty acids



Patented Jan. 18, 1949 CONCENTRATION OF NONSULFIDE, NON WITH NITRIC ACID TREATED FATTY ACIDS James B. Duke, Lakeland, Fla., assignor to Minerals Separation North American Corporation, New York, N. Y., a corporation of Maryland No Drawing. Application February 2, 1948,

Serial No. 645,244

'SILICATE ORES 14 Claims. 1

This invention relates to the concentration of ores. Particularly, it relates to separating the components with a view to recovering the valuable constituents of a wide variety of non-sulfide ores and minerals. More particularly, it relates to those ores in which non-sulfide, non-silicate minerals are mixed with silicious gangue, or in which silicate minerals are admixed with quartz. Among such ores and minerals to the beneficiation of which the invention is particularly adapted are phosphate, iron ore, barite, calcite, feldspar, fluorspar, manganese ores, kyanite, industrial sands, ilmenite, rutile, and zircon.

The invention vutilizes my discovery of new collector reagents of the anionic type, hereinafter described, which are particularly eil'ective in beneficiating non-sulfide ores and minerals. One advantage of these new collector reagents is that they are generally effective in ore pulps which may have a wide range of pH involving acid, neutral and alkaline conditions. A particular advantage of these new reagents is that they require the use of less pH adjusting reagents (alkalis and acids) than other types of anionic reagents known to the art. Another advantage of these reagents is that they are generally self-frothing reagents and frequently do not require the addition of frothers. Still another advantage of these new reagents is their efliciency as collectors, since they produce concentrates of high grade with high recovery by the use of only very small amounts of the reagent.

In general the new collector reagents utilized in the present invention comprise the reaction products resulting from the interaction of strong nitric acid and fatty acid, the hydrocarbon chain of which contains seven or more carbon atoms. These reaction products will be hereinafter called nitric acid treated fatty acid materials. The

fatty acids from which the said collector reagents are produced by the action thereon of strong nitric acid, may be unsaturated fatty acids and mixtures of saturated and unsaturated fatty acids. These collector reagents may be produced by the action of nitric acid on animal or vegetable fatty acids, such as red oil (oleic acid), fish-oil fatty acids, cod-liver oil fatty acids, cotton-seed oil fatty acids, castor-oil fatty acids, and mixtures of fatty and resin acids such as tall oil, which is a I productobtained from the waste liquor or the paper pulp industry sold under various names. I have found the reaction products of concentrated nitric acid with oleic acid, tall oil fatty and resin acids, and fish-oil fatty acids to be particularly eflective as collectors.

The new collector reagents can be readily pre pared by reacting the fatty acid material with concentrated nitric acid. The mixture of fatty acid material and nitric acid is heated with agitation until a definite reaction takes place. This reaction is fairly violent and can be readily observed. After the completion of the first reaction,

. the material is again heated to a somewhat higher temperature, at which a second reaction takes place. As soon as this second reaction occurs the heat is removed, and there will be a further rise in temperature to a certain extent. The product of the reaction is then allowed to cool and is ready for use as a flotation collector reagent. When red oil (oleic acid) is employed in making the nitric acid treated fatty acid, the reaction product is soluble in hydrocarbon oils and is preferably used in solution in such oils. When tall oil fatty and resin acids are reacted with nitric acid to produce the collectors of this invention the resulting product may be completely or only partially soluble in hydrocarbon oils, When fish-oil fatty acid is employed, the reaction product, being insoluble in hydrocarbon oil, may be used as a flotation collector in solution in other organic solvents such as, for instance dioxan. While it is generally preferable to use the flotation collectors of this inventiondissolved in either hydrocarbon oils, or other organic solvents, they may pulp.

The proportions of nitric acid to fatty acid material will vary according to the strength of the nitric acid and the particular fatty acid material used, and should preferably amount to 5 or more parts of nitric acid to parts of fatty acid material, by weight, although I have found no advantage in adding more than 15 to 20 parts of nitric acid. I have found that about 10 to 1.5 parts of concentrated nitric acid to 100 parts of fatty acid material, by weight, generally produces the best collector reagent. Any commercial nitric acid of sumcient strength to react with the fatty acid [material canbe utilized. What is known commercially as concentrated nitric acid was used in the making of the collector'reagents employed in the tests hereinafter described. Agua regia (a mixture of 3 parts hydrochloric acid to 1 part nitric acid) may be used instead of concentrated nitric acid, and probably acts by virtue of its nitric acid content.- The above described methods of preparing the nitric acid treated fatty acid materials may of course be modified without departing from the spirit of the invention.

Concentrating processes of known types in which the collector reagents herein described are useful, include froth-flotation concentration by the use of flotation cells, and agglomeration with separation by the use of shaking tables, underwater screens, moving belts, pneumatic launders, revolving perforated cylinders, etc. Other reagents may be used in conjunction with the said collector reagents, appropriate'to the particular ores being treated and to the processes used, such as frothers, conditioners and modifiers. Waterinsoluble, non-frothing hydrocarbon oils such as fuel oil, kerosene, mineral oil, etc, are particularly useful in conjunction with these collector reagents. The mineral oils which have been purified for medicinal use make good laboratory standard inert hydrocarbon oils generally equivalent to other such oils as mentioned above. Alkalis and acids or other pH adjusters may also be employed with these collector reagents; and they may advantageously be used in step concentration procedures.

The following examples illustrate processes of ore concentration utilizing as collector reagents the nitric acid treated fatty acid materials hereinbefore described. Examples 1 to 9 illustrate the effectiveness of these collector reagents in the concentration of phosphate from phosphate ores. In the tests reported as Examples 10 to 15, a variety of ores and minerals were concentrated or purified using typical nitric acid treated fatty acid materials, thereby illustrating the general applicability of said reagents to ores of the classes referred to above. In all of the examples, the amounts of reagents used are given in pounds per ton of solids in the feed.

Example 1 2.0 lbs. of nitric acid treated red oil resulting from reaction between only 5 parts of concentrated nitric acid and 100 parts of red 011. After froth-flotation treatment, the results were as follows:

Per cent Per cent Per cent Per cent Pfoducts wt. B. P. L. insol. rec.

It will be obvious that the results of this test were poor from the standpoint of recovery, doubtless due to the small proportion of nitric acid used in making the nitric acid treated red oil.

Example 2 In this test, conditions were the same as in Example 1 except that 10 parts of nitric acid (double were as follows:

Per cent Per cent Per cent Per cent Products wt. B. P. L iusol rec.

- 100.0 35.6 100. 40.5 77.6 Y 4.4 88. 2. 2 52. 5 34. 7 3. 6. ll 16. 7 3. 50. 7 3.7 5.

It will be observed that the results of this test were, much better than those of Example 1 so far as recovery is concerned, doubtless due to the larger amount of nitric acid employed in making the nitric acid treated red oil.

Example 3 After the froth-flotation treatment, the results f of this test were as follows:

Per cent Per cent Per cent Per cent Products wt. P. L. insoL. rec.

I 100. 0 35. 9 100. 0 43. 0 76. 9 4. 7 92. l 2. 4 37. 2 52. 3 2. i 8. 8 8. l 2. 0 48. 8 2. 6 3. 4

It will be apparent that the results of this test were even better than the results in Example 2 from the standpoint of recovery, and that the grade of the concentrate was satisfactory though not quite as high as in Examples 1 and 2.

Erample 4 In this test, all conditions were the same as in Examples 1, 2 and 3 except that 20 parts of nitric acid (four times the amount in Example 1) to parts of red oil were used in making the nitric acid treated red oil, and except that the amount of the latter was only 1.5 lbs. per ton of feed. After the froth-flotation treatment, the results of this test were as follows:

Per cent Per cent Per cent Per cent Products Wt. 13. lnsol. rec.

100. 0 7 101). i) 43. 6 76. 4 4. 9 J3. 3 2. 3 33. 4 55. 8 2. 2 8.4 7.9 1.8 Tail 45.7 2.1 2.7

It will be noted that the results of this test are about the same asthe results of Example 3, which seems to prove that 15 to 100 is about the best proportion of nitric acid to red oil for the making of nitric acid treated red oil'for use as a collector in the concentration of phosphate.

Example 5 the following results:

011 and only 0.8 lb. of the reaction product from 15 parts of concentrated nitric acid to 100 parts of red oil. After the froth-flotation treatment, the results of this test were as follows:

lcr ccnt Per cent Per eon Per cent Products wt. B. P. L. insol. 1 rec.

Comparison of the results of this test with the results in Example 3, shows a substantial increase both in the grade of the phosphate concentrate Example 6 This test illustrates the concentrationof phosphate by agglomeration tabling methods. In this test, the feed was deslimed phosphatic sands from which the minus 35 mesh particles had been eliminated. This feed was conditioned at approximately 70% solids for 2 minutes with 0.3 lb. caustic soda, 4.2 lbs. mineral oil and 1.7 lbs. of collec- F ap:

tor reagent produced by the reaction of concentrated nitric acid and red oil in the proportions of 15 to 100. The thus conditioned feed was subjected to concentration on' a shaking table, with It will be observed that these results were satisfactory from the standpoints of both grade and recovery.

' Example 7 This test illustrates the use of the reaction product 'of nitric acid and tall oil fatty and resin acids, in the concentration of phosphate ore.

Per cent er cent Per cent 1 rmmct's wt. B. I I. rue.

F0011 100.0 36.3 100.1) Cone 43.1 78. 8 93. h l. 2 216.9 1.2 3. 9 l8. 8 2. (l 5]. 8 2. 2 ll. 2

It will be noted that the phosphate concentrate thus produced was highly satisfactory as to both grade and recovery.

Example 8 1 This test illustrates the use of the reaction product of nitric'acid and fish oil fattly acids in the concentration of phosphate ore. In this test, the phosphate feed was the same as in Example 1, and was conditioned at about solids for 2 minutes with 2.5 lbs. mineral oil and 2.0 lbs. of the product of the reaction of nitric acid with fish oil fatty acids, in the proportion of 5 to 100, as a 10% solution in dioxan. The thus-conditioned feed was submitted to froth-flotation treatment with the following results:

Per cent Per cent For ('Alll. Per cent Products w B. P inscl. rec.

100. (l 3". i) 100. 0 42.0 77.4 5. i 01.5 1.2 39.6 1.3 5. l l4. 1 2. i 50.9 3.6 5.1

It is evident that the phosphate concentrate thus produced was satisfactory as to both grade and recovery.

Example 9 In this test, all conditions were the same as in Example 8, except that 0.4 lb. caustic soda was used along with the nitric acid treated fatty acids of which only 0.8 lb. was employed, the amount of mineral oil being 2.5 lbs. as in Example 8. The results of this test were as follows:

Percent Per cent Per cont Percent wt. 73. I L. insol, rot.

Fcvll 100.0 35.4 1mm one 38. 5 79. (3 2.7 813. 5 id 2.4 47.] 3.2 'luil I fiiLl I (3.2 10.3

This test, as'compared with Example 8, indicates that the useof caustic soda permits reduction in the amount of nitric acid treated fish .oil fatty acids employed, and results in a substantially higher grade of phosphate concentrate; although recovery was somewhat lower. a

Example 10 I This example illustrates the use of nitric acid treated red oil in the concentration of low grade oxidized iron ore. The ore was conditionedat about 73% solids for 4 minutes with 9.1 lbs. mineral oil and 2.4 lbs. of the product of the reaction of nitric acid with red oil in the proportions of 10 to 100. The results were as follows:

, lol'ccnt lvrvvnlv lcrcvnl. lvrl'cnl. Pmdmt wt. Po insol. rec.

100.0 20. It 100.0 20. .i m. 7 7. 5/ on. u 2. a 42.1 :24. '3 s. 4 5.0 21.7 5.0 15.2 10.1 7,4 so. 2 7. 4 2n. 7

(-cnc.-Mi(l-3.. 22.0 cm 10.5; -.ma.0

It will be noted that the iron concentrate was of commercial grade, although the recovery'was rather low.'

' Example 11 This test illustrates the usefulness of nitric acid treated red oil in .the concentration of ba- -rite ore. The feed was a ground barite ore con taining o're' particIesless than 35' mesh. which had been deslimed. This feed was conditioned aaeaara 7 at about 72% solids in 2 minutes with 4.7 lbs. mineral oil and 1.0 lb. of the product of the reaction of nitric acid with red oil in the proportions of 15 to 100. The results of this test were as follows:

It will be seen that the barite concentrate was highly satisfactory as to both grade and recovery.

Example 12 In this test, conditions were the same as in Example 11, except that 0.2 lb. caustic soda was employed along with the mineral oil and nitric acid treated red oil. The results of this test were as follows:

Per cent Per cent Per cent Per cent Pmduc wt. Baso. sioi I rec.

Feed 100. 69. 0 100. 0 54. 2 95. 9 1. 4 75. 4 7. 5 98. 1 2. 0 10. 2 6. 2 85. 5 7. 4 7. 7 5. 3 56. 4 4. 3 26. 8 6. 3 2. 4

Conc.-Mid-3-Mid2 67. 9 94. 7 r 2. 2 93. 3

It will be noted that the use of caustic soda, along with the other reagents, resulted in a considerably higher grade of concentrate and only a slightly reduced recovery.

Example 13 This test illustrates the usefulness of nitric acid treated red oil in the froth-flotation of ferruginous impurities away from an industrial sand, to produce a purified sand useful for glassmaking. The feed was an industrial sand which had been washed. This feed was conditionad at about 68% solids for 2 minutes with 0.2 lb. caustic soda and 1.0 lb. nitric acid treated red oil produced by the reaction of nitric acid and red oil in the proportions of 15 to 100. The thusconditioned feed was subjected to froth-flotation treatment with the following results:

Percent Percent F6102 Pmducts wt F820: distribution eed 100. 0 0. 161 100. 0 Froth Product 6. 0 2. 74. 5 Machine Discharge 94. 0 0.044 25. 5

\ Example 14 This test illustrates the remarkable usefulness of the reagents of this invention in separating heavy minerals from quartz sand, producing in the same operation a high grade and recovery of heavy mineral as a floating concentrate and a very high quality and recovery 0t glass sand as a machine discharge. Raw sands used for this test were Florida beach sands conore from Virginia was comminuted to mesh 8 taining about 22% of heavy minerals composed of ilmenite, rutile, kyanite and zircon. The beach sands were conditioned at about 70% solids for 2 minutes with only 1.0 lb. nitric acid treated red oil produced by the reaction of. nitric acid 7 and red oil in the proportions of 15 to 100. The thus-conditioned beach sands were then subjected to froth-flotation treatment with the following results:

" Per cent dis- Per Per- Per- Percent tribution Products cent cent cent total wt. sink float Fe Sink Float heavy minerals with a grade of 97.4%; and aglass. sand product containing only .012% Fe and representing about 96.8% recovery of sand.

Emqmple 15 This test illustrates the usefulness of nitric acid treated red oil as a flotation reagent for the concentration of kyanite from an ore consisting largely of kyanite and quartz. A kyanite and largely deslimed. This ore was then conditioned at about 67% solids for two minutes with .5 lb. sodium silicate and 1.2 lbs. nitric acid treated red oil in the proportions of 15:100.-

The thus conditioned ore was then subjected to froth-flotation treatment with the following results:

Per- Per- Per- Per cent Percent Products cent cent cent total distribuwt. sink float Fe tion sink The results of this test show a high grade kyanite concentrate representing 70.2% recovery, and i1- lustrates the concentration of a silicatemineral from quartz.

What is claimed is: I

1. The process of separating the components of an ore of the class consisting of non-sulfide, nonsilicate minerals mixed with silicious gangue and silicate minerals admixed with quartz, which comprises subjecting an aqueous pulp of the ore in a suitably divided state to a concentrating operation in the presence of the reaction product resulting from heating a mixture in which the principal ingredient is unsaturated fatty acid material containing hydrocarbon chains of '7 or more carbon atoms and the minor ingredient. is nitric acid.

2. The process of separating the components of an ore of the class consisting of non-sulfide, non-silicate minerals mixed with silicious gangue .and silicate minerals admixed with quartz,

which comprises conditioning an aqueous pulp of the ore in a suitably divided state with a mineral oil and the reaction product resulting from heating a mixture in which the principal ingredient is unsaturated fatty acid material containing hydrocarbon chains of 7 or more carbon atoms and the minor ingredient is nitric acid, and subjecting. the thus conditioned ore pulp to a concentrating operation to separate the ore constituents.

3. The proces of separating the components of an ore of the class consisting of non-sulfide,

non-.silicate minerals mixed with silicious gangue and silicate minerals admixed with quartz, which comprises conditioning an aqueous pulp of the ore in a suitably divided state with a mineral oil, an alkali and the reaction product resulting from heating a mixture in which the principal ingredient is unsaturated fatty acid material containing hydrocarbon chains of '7 or more carbon atoms and the minor ingredient is nitric acid, and subjecting the thus conditioned ore pulp to a concentrating operation to separate the ore' constituents.

4. The process of claim 1 employing oleic acid as the unsaturated fatty acid material. 5. The process of claim 1 employing a mixture of fatty and resin acids as the unsaturated fatty acid material.

6. The process of claim 1 employing fish oil fatty acids as the unsaturated fatty acid material material.

. 10 witha mineral oil and the reaction product resulting from heating a mixture in which the principal ingredient is unsaturated fatty acid material containing hydrocarbon chains of 7 or more carbon atoms and the minor ingredient is nitric acid, and subjecting the thus conditioned ore pulp to a concentrating operation-to produce a barite concentrate.

10. The process of claim 9 employing an alkali" along with the mineral oil and said reaction product.

11. The process of claim *1 applied to a glass sand to reduce the ferruginous impurities therein 7. The process of concentrating phosphate from a phosphate ore which comprises conditioning an aqueous pulp of the ore in a suitably divided state with a mineral oil and the reaction product resulting from'heating a mixture in which the principal ingredient is unsaturated fatty acid material containing hydrocarbon chains of 7 or more carbon atoms and the minor ingredient is nitric acid, and subjecting the thus conditioned ore pulp to a. concentrating operation to produce a phosphate concentrate. I

8. The process of claim 7 employing an alkali along with the mineral oil and said reaction product.

9. The process of concentrating barite from a barite ore which comprises conditioning an aqueous pulp of the ore in a suitably divided state taining hydrocarbon chains of 7 or morecarbon atoms, and not more than about 20 parts of nitric acid. JAMES B. DUKE.

REFERENCES CITED The following references are of record in the a file of this patent:

UNITED STATES PATENTS Number Name Date 2,099,120 2,105,826 Tartaron Jan. 18, 1938 Ralston July 5, 1938 Ralston Mar. 7,1939

Price Dec. 19, 1944 Kirby Nov. 16, 1937 

